Comparison of three videolaryngoscopes for double-lumen tubes intubation in simulated easy and difficult airways: a randomized trial

BACKGROUND: The King Vision™ (KVL) and Airtraq® videolaryngoscopes may reduce the time to double lumen tube (DLT) intubation compared to the GlideScope® and MacIntosh in simulated easy and difficult airways.METHODS: Twenty-one staff anesthesiologists with limited prior experience in using videolaryngoscopes for DLT intubation were assigned randomly to insert a DLT using the MacIntosh, GlideScope®, Airtraq® and KVL videolaryngoscopes on easy and difficult airway simulators in a randomized crossover order. Time to DLT intubation, laryngoscopic view, intubation difficulty, optimizing manoeuvers and failure to intubation — defined as an attempt taking longer than 150 s — were recorded.RESULTS: The three videolaryngoscopes had comparable times to intubation and glottis visualization in both scenarios. Compared with the MacIntosh, the KVL had longer intubation times in the simulated easy airway scenario (mean 9.2 vs. 21.1 s, respectively, P<0.001). In both scenarios, the Airtraq® took a longer intubation time than the MacIntosh (P<0.001 and P=0.019, respectively). The GlideScope® was easier to use than the Airtraq® and KVL in the easy airway scenario (P=0.021 and P=0.001, respectively). The KVL had higher intubation difficulty scores than the GlideScope® and Airtraq® (P=0.002 and P=0.008, respectively) in both scenarios and required more frequent optimizing manoeuvers than the GlideScope® (P=0.012) in the simulated easy airway. Two participants failed to intubate the difficult airway simulator; one with the MacIntosh and the other with the KVL.CONCLUSIONS: The Airtraq® and non-channeled KVL required more time over the MacIntosh for DLT intubation, as a primary outcome, but the success rates for the 3 videolaryngoscopes were very high.